US4479156A - Magnetic disk recorder - Google Patents

Magnetic disk recorder Download PDF

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Publication number
US4479156A
US4479156A US06/375,090 US37509082A US4479156A US 4479156 A US4479156 A US 4479156A US 37509082 A US37509082 A US 37509082A US 4479156 A US4479156 A US 4479156A
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United States
Prior art keywords
head
magnetic
magnetic disk
magnetic head
chips
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US06/375,090
Inventor
Munehito Kumagai
Shigehisa Suzuki
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Mitsubishi Electric Corp
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Mitsubishi Electric Corp
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Assigned to MITSUBISHI DENKI KABUSHIKI KAISHA reassignment MITSUBISHI DENKI KABUSHIKI KAISHA ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: KUMAGAI, MUNEHITO, SUZUKI, SHIGEHISA
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    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/012—Recording on, or reproducing or erasing from, magnetic disks
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/48—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
    • G11B5/488—Disposition of heads
    • G11B5/4886—Disposition of heads relative to rotating disc
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/48—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
    • G11B5/56—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed with provision for moving the head support for the purpose of adjusting the position of the head relative to the record carrier, e.g. manual adjustment for azimuth correction or track centering

Definitions

  • T p denote the width of each track
  • T p it is favorable to set the internal distance between the head of Channel 1 and that of Channel 2 at a value three times greater than the track width T p .
  • the head of Channel 1 corresponds to the track of the outermost periphery of the magnetic disk, and the head of Channel 2 to the third track as reckoned from the outermost periphery, the track of the outermost periphery being excepted.
  • An object of this invention is to provide a recording system which makes all of tracks usable when such an azimuth recording system is applied to a magnetic disk recorder.
  • This invention includes a magnetic disk recorder which applies an azimuth recording system which can use all of the tracks of a magnetic disk.
  • a plurality of magnetic head chips each of which is formed with a head gap having a predetermined azimuth angle, are respectively assembled into separate head sliders along with dummy heads, and the head sliders are driven by separate actuators.
  • FIG. 2 is a perspective view of a prior art head slider
  • FIG. 4 is a pattern diagram showing tracks recorded on a magnetic disk by the prior art magnetic head shown in FIG. 3, and the magnetized directions thereof.
  • FIGS. 5(I) and 5(II) are plan views showing a pair of head sliders according to the present invention in which magnetic head chips of Channel 1 and Channel 2 are respectively assembled separately;
  • FIG. 6 is a pattern diagram showing tracks recorded on a magnetic disk by the magnetic head according to the present invention, and the magnetized directions thereof.
  • the tracks al and bl are first recorded by the respective head gaps 2 and 4 of the magnetic head chips 1 and 3. Subsequently, the head slider 7 is moved toward the inner periphery of the magnetic disk 9 by a step equal to 2 ⁇ T p along a line B--B' which passes through the rotational center ⁇ of the magnetic disk 9, whereupon the tracks a2 and b2 are recorded by the respective head gaps 2 and 4. Thereafter, while the head slider 7 is being moved toward the inner periphery by steps of 2 ⁇ T p in succession, the tracks are recorded so that all the tracks may be finally recorded.
  • FIGS. 5(I) and 5(II) show an embodiment of this invention, in which symbols 1' and 3' indicate magnetic head chips respectively having head gaps 2' and 4' of azimuth angles ⁇ and ⁇ , symbols 7' and 7" denote head sliders which are separate from each other, and numeral 10 denotes a dummy head.
  • FIG. 6 is a pattern diagram which shows the tracks which are recorded on the surface of a magnetic disk 9' by the magnetic head of this invention, and further show the magnetized directions thereof. This invention is characterized in that, as shown in FIGS.
  • the magnetic head chip 1' of Channel 1 having a head gap 2' with an azimuth angle ⁇ which is positive in a clockwise direction with respect to a line A--A' which is perpendicular to the plane of the head chip and the magnetic head chip 3' of Channel 2 having a head gap 4' which an azimuth angle ⁇ which is negative in a clockwise direction with respect to a line A--A' which is perpendicular to the plane of the head chip.
  • the magnetic head chips are respectively assembled into the separate head sliders 7' and 7", and these head sliders are respectively mounted on separate actuators (not shown).

Abstract

A magnetic disk recorder which applies an azimuth recording system and which can use all of the tracks of a magnetic disk. In particular, a plurality of magnetic head chips, each of which is formed with a head gap having a predetermined azimuth angle, are respectively assembled into separate head sliders along with dummy heads, and the head sliders are driven by separate actuators.

Description

BACKGROUND OF THE INVENTION
In recorders employing tapes, such as VTRs, the azimuth recording system in which head gaps are inclined with respect to the direction of tracks has been adopted in order to enhance the recording density.
In case this recording system is applied to a magnetic disk recorder with the intention of enhancing the recording density in the radial direction of a magnetic disk, there has been the problem that all the tracks of the magnetic disk cannot be used and that unrecorded tracks are left.
Let's consider a recording operation using a magnetic head in which the head gap of Channel 1 and that of Channel 2 have unequal angles (the so-called azimuth angles) with respect to the widthwise direction of the tracks of a magnetic disk. Letting Tp denote the width of each track, it is favorable to set the internal distance between the head of Channel 1 and that of Channel 2 at a value three times greater than the track width Tp. First, the head of Channel 1 corresponds to the track of the outermost periphery of the magnetic disk, and the head of Channel 2 to the third track as reckoned from the outermost periphery, the track of the outermost periphery being excepted. Subsequently, the magnetic head is moved 2·Tp so that the head of Channel 1 may correspond to the second track as reckoned from the outermost periphery and that the head of Channel 2 may correspond to the fifth track. Furthermore, the magnetic head is successively moved inward at steps of 2·Tp. Thus, most of the tracks are successively recorded.
However, the first track as reckoned from the outermost periphery and the first track as reckoned from the innermost periphery are left unrecorded.
An object of this invention is to provide a recording system which makes all of tracks usable when such an azimuth recording system is applied to a magnetic disk recorder.
SUMMARY OF THE INVENTION
This invention includes a magnetic disk recorder which applies an azimuth recording system which can use all of the tracks of a magnetic disk. In particular, a plurality of magnetic head chips, each of which is formed with a head gap having a predetermined azimuth angle, are respectively assembled into separate head sliders along with dummy heads, and the head sliders are driven by separate actuators.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1(I) and 1(II) are perspective views showing prior art magnetic head chips of Channel 1 and Channel 2, respectively;
FIG. 2 is a perspective view of a prior art head slider;
FIG. 3 is a plan view showing the state in which the magnetic head chips of Channel 1 and Channel 2 having unequal azimuth angles are assembled into the prior art single head slider;
FIG. 4 is a pattern diagram showing tracks recorded on a magnetic disk by the prior art magnetic head shown in FIG. 3, and the magnetized directions thereof.
FIGS. 5(I) and 5(II) are plan views showing a pair of head sliders according to the present invention in which magnetic head chips of Channel 1 and Channel 2 are respectively assembled separately;
FIG. 6 is a pattern diagram showing tracks recorded on a magnetic disk by the magnetic head according to the present invention, and the magnetized directions thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENT
First, the technique on which the present invention is grounded will be described with reference to FIGS. 1(I) and 1(II), FIG. 2, FIG. 3 and FIG. 4.
In FIGS. 1(I) and 1(II), numeral 1 designates a magnetic head chip of Channel 1 having a head gap 2 of an azimuth α which is defined to be positive in a clockwise direction with respect to a line A--A' which is perpendicular to a head chip plane, while numeral 3 designates a magnetic head chip of Channel 2 having a head gap 4 of an azimuth angle β which is defined to be negative in a clockwise direction with respect to a line A--A' which is perpendicular to a head chip plane. Symbol Tw indicates the track width of each of the magnetic head chips 1 and 3, and numeral 5 indicates a window for inserting a coil 6. FIG. 2 is a perspective view of a head slider 7, which is formed with a pair of mounting windows 8 and 8 for inserting and holding the respective magnetic head chips 1 and 3. FIG. 3 is a plan view showing a magnetic head for azimuth recording in which both the magnetic head chips 1 and 3 are inserted into the mounting windows 8 and 8 of the head slider 7 and then bonded and fixed. FIG. 4 shows tracks recorded on the surface of a magnetic disk 9 by the abovenoted magnetic head, and further shows the magnetized directions thereof. In FIG. 4, symbols al ˜ an indicate the tracks recorded by the head gap 2 of the magnetic head chip 1, while symbols bl ˜ bn indicate the tracks recorded by the head gap 4 of the magnetic head chip 3. Each of the magnetic head chips 1 and 3 has the track width Tw., and these magnetic head chips are assembled at a center distance P. Letting Tp denote the pitch of the tracks recorded on the magnetic disk 9, the center distance is set at P= 3Tp in this example.
Referring to FIG. 4, the tracks al and bl are first recorded by the respective head gaps 2 and 4 of the magnetic head chips 1 and 3. Subsequently, the head slider 7 is moved toward the inner periphery of the magnetic disk 9 by a step equal to 2·Tp along a line B--B' which passes through the rotational center φ of the magnetic disk 9, whereupon the tracks a2 and b2 are recorded by the respective head gaps 2 and 4. Thereafter, while the head slider 7 is being moved toward the inner periphery by steps of 2·Tp in succession, the tracks are recorded so that all the tracks may be finally recorded.
The prior-art azimuth-recording magnetic head described above, however, has the disadvantage that unrecorded tracks e and f with one track belonging to each of the innermost periphery and outermost periphery of the magnetic disk are left as illustrated in FIG. 4.
This invention has been made to obviate such a drawback, and is intended to provide an azimuth-recording magnetic head which can record tracks on a magnetic disk surface without any waste.
FIGS. 5(I) and 5(II) show an embodiment of this invention, in which symbols 1' and 3' indicate magnetic head chips respectively having head gaps 2' and 4' of azimuth angles α and β, symbols 7' and 7" denote head sliders which are separate from each other, and numeral 10 denotes a dummy head. FIG. 6 is a pattern diagram which shows the tracks which are recorded on the surface of a magnetic disk 9' by the magnetic head of this invention, and further show the magnetized directions thereof. This invention is characterized in that, as shown in FIGS. 5(I) and 5(II), the magnetic head chip 1' of Channel 1 having a head gap 2' with an azimuth angle α which is positive in a clockwise direction with respect to a line A--A' which is perpendicular to the plane of the head chip and the magnetic head chip 3' of Channel 2 having a head gap 4' which an azimuth angle β which is negative in a clockwise direction with respect to a line A--A' which is perpendicular to the plane of the head chip. The magnetic head chips are respectively assembled into the separate head sliders 7' and 7", and these head sliders are respectively mounted on separate actuators (not shown).
FIG. 6 shows the tracks recorded on the magnetic disk 9' by the magnetic head according to this invention, as well as the magnetized directions thereof, wherein al' ˜ an' indicate the tracks recorded by the head gap 2' of the magnetic head chip 1', and bl' ˜ bn' indicate the tracks recorded by the head gap 4' of the magnetic head chip 3'. Each of the magnetic head chips 1' and 3' has a track width Tw. Letting Tp denote the pitch of the tracks recorded on the magnetic disk 9', the actuators on which the head sliders 7' and 7" are individually mounted are initially set so that the other head chip 3' may be moved closer to the inner periphery than one head chip 1' by the track pitch tp.
Therefore, according to the azimuth-recording magnetic head of this invention, the tracks al' and bl' are first recorded by the respective head gaps 2' and 4' of the magnetic head chips 1' and 3'. Subsequently, the head sliders 7' and 7" are moved toward the inner periphery of the magnetic disk 9' by steps of 2·Tp by the respective actuators along a line B--B' which passes through the rotational center φ of the magnetic disk 9', whereupon the tracks a2' and b2' are respectively recorded by the head gaps 2' and 4'. Thereafter, while the head sliders are being moved toward the inner periphery by the steps of 2·Tp in succession, the tracks are recorded on the magnetic disk 9'. This invention has the excellent effect that the unrecorded tracks e and f with one track belonging to each of the outermost periphery and the innermost periphery of the magnetic disk as in the foregoing prior art are not left unused.

Claims (2)

What is claimed is:
1. A magnetic disk recorder comprising: a plurality of magnetic head chips, each of which is formed with a head gap having a predetermined azimuth angle; at least two separate head sliders, each of which having one of said plurality of magnetic head chips assembled thereon; and at least two separate actuators, each of which actuates a respective one of said head sliders by associated connecting means,
said azimuth angle of said head gap of one of said plurality of magnetic head chips is defined to be positive in a clockwise direction with respect to a radial line extending from the center of said magnetic disk and wherein said azimuth angle of said head gap of another of said magnetic head chips is defined to be negative in a clockwise direction with respect to said radial line, said magnetic head chips having said positive azimuth angle is assembled on one of said head sliders, while said magnetic head chip having said negative angle is assembled on another of said head sliders, wherein two of said magnetic head chips are arranged at a distance which is equal to a track pitch Tp, and said head chips are moved by said actuators at 2·Tp steps in succession.
2. A magnetic disk recorder according to claim 1, further comprising at least two dummy heads, each of which is assembled in a respective one of said head sliders along with said magnetic head chips.
US06/375,090 1981-05-11 1982-05-05 Magnetic disk recorder Expired - Lifetime US4479156A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP56-70555 1981-05-11
JP56070555A JPS57186229A (en) 1981-05-11 1981-05-11 Magnetic head for azimuth recording

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US4479156A true US4479156A (en) 1984-10-23

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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4896220A (en) * 1986-07-28 1990-01-23 Fuji Photo Film Co., Ltd. Magnetic recording method and magnetic recording head used therefor
US4945427A (en) * 1988-06-13 1990-07-31 International Business Machines Corporation Magnetic disk recording with variable track width and variable track density
US5307217A (en) * 1992-06-24 1994-04-26 Digital Equipment Corporation Magnetic head for very high track density magnetic recording
US5371638A (en) * 1992-06-24 1994-12-06 Digital Equipment Corporation Servo method and apparatus for very high track density magnetic recording by adjusting head position based on servo information read from adjacent track
US5949604A (en) * 1992-06-24 1999-09-07 Quantum Corporation Method of writing and reading servo on tracks having a longitudinal gap
US6183618B1 (en) 1999-02-02 2001-02-06 Kemet Electronics Corporation Process for treating impregnated electrolytic capacitor anodes
US20050083602A1 (en) * 2003-10-20 2005-04-21 Saliba George A. Servo methods and systems using existing data structures and medium edge position
US20050083600A1 (en) * 2003-10-20 2005-04-21 Faramarz Mahnad Methods and systems for magnetic recording
US20050083601A1 (en) * 2003-10-20 2005-04-21 Faramarz Mahnad Servo methods and systems using existing data structures and optical masks
US20050088776A1 (en) * 2003-10-20 2005-04-28 Saliba George A. Diffractive position sensors and control systems
US20050088770A1 (en) * 2003-10-20 2005-04-28 George A. Saliba Electromagnetic void-sensing probes and position control systems
US20050094308A1 (en) * 2003-10-20 2005-05-05 Faramarz Mahnad Servo methods and systems using masked medium edge position sensors
US20050270687A1 (en) * 2004-06-04 2005-12-08 James Zweighaft Dual source tracking servo systems and associated methods
US20060103968A1 (en) * 2004-11-12 2006-05-18 Jurneke Joe K Dynamic skew compensation systems and associated methods
US20060209450A1 (en) * 2005-03-18 2006-09-21 Quantum Corporation Auto-servo tape system and associated recording head
US20080266705A1 (en) * 2007-04-25 2008-10-30 Quantum Corporation Servo error detection and compensation utilizing virtual data tracking servo methods

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS613304A (en) * 1984-06-18 1986-01-09 Akai Electric Co Ltd Magnetic disc recording and reproducing device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4314290A (en) * 1977-06-16 1982-02-02 Burroughs Corporation Di-bit recording technique and associated servo indicia
US4321634A (en) * 1977-10-07 1982-03-23 Thomson-Csf Endless magnetic tape video recorder/player with head centering means
US4334252A (en) * 1979-03-20 1982-06-08 Mitsubishi Denki Kabushiki Kaisha Magnetic recording and reproducing head arrangement
US4338631A (en) * 1977-02-17 1982-07-06 Victor Company Of Japan, Ltd. Video signal, speed-change reproducing system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4338631A (en) * 1977-02-17 1982-07-06 Victor Company Of Japan, Ltd. Video signal, speed-change reproducing system
US4314290A (en) * 1977-06-16 1982-02-02 Burroughs Corporation Di-bit recording technique and associated servo indicia
US4321634A (en) * 1977-10-07 1982-03-23 Thomson-Csf Endless magnetic tape video recorder/player with head centering means
US4334252A (en) * 1979-03-20 1982-06-08 Mitsubishi Denki Kabushiki Kaisha Magnetic recording and reproducing head arrangement

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4896220A (en) * 1986-07-28 1990-01-23 Fuji Photo Film Co., Ltd. Magnetic recording method and magnetic recording head used therefor
US4945427A (en) * 1988-06-13 1990-07-31 International Business Machines Corporation Magnetic disk recording with variable track width and variable track density
US5307217A (en) * 1992-06-24 1994-04-26 Digital Equipment Corporation Magnetic head for very high track density magnetic recording
US5371638A (en) * 1992-06-24 1994-12-06 Digital Equipment Corporation Servo method and apparatus for very high track density magnetic recording by adjusting head position based on servo information read from adjacent track
US5949604A (en) * 1992-06-24 1999-09-07 Quantum Corporation Method of writing and reading servo on tracks having a longitudinal gap
US6183618B1 (en) 1999-02-02 2001-02-06 Kemet Electronics Corporation Process for treating impregnated electrolytic capacitor anodes
US7136255B2 (en) 2003-10-20 2006-11-14 Quantum Corporation Servo methods and systems using masked medium edge position sensors
US20050083602A1 (en) * 2003-10-20 2005-04-21 Saliba George A. Servo methods and systems using existing data structures and medium edge position
US20050083601A1 (en) * 2003-10-20 2005-04-21 Faramarz Mahnad Servo methods and systems using existing data structures and optical masks
US20050088776A1 (en) * 2003-10-20 2005-04-28 Saliba George A. Diffractive position sensors and control systems
US20050088770A1 (en) * 2003-10-20 2005-04-28 George A. Saliba Electromagnetic void-sensing probes and position control systems
US20050094308A1 (en) * 2003-10-20 2005-05-05 Faramarz Mahnad Servo methods and systems using masked medium edge position sensors
US20050083600A1 (en) * 2003-10-20 2005-04-21 Faramarz Mahnad Methods and systems for magnetic recording
US7149050B2 (en) 2003-10-20 2006-12-12 Quantum Corporation Diffractive position sensors and control systems
US7085095B2 (en) 2003-10-20 2006-08-01 Quantum Corporation Electromagnetic void-sensing probes and position control systems
US7102845B2 (en) 2003-10-20 2006-09-05 Quantum Corporation Servo methods and systems using existing data structures and medium edge position
US7139152B2 (en) 2003-10-20 2006-11-21 Quantum Corporation Servo methods and systems using existing data structures and optical masks
US7116514B2 (en) 2003-10-20 2006-10-03 Quantum Corporation Methods and systems for magnetic recording
US20050270687A1 (en) * 2004-06-04 2005-12-08 James Zweighaft Dual source tracking servo systems and associated methods
US7184233B2 (en) 2004-06-04 2007-02-27 Quantum Corporation Dual source tracking servo systems and associated methods
US20060103968A1 (en) * 2004-11-12 2006-05-18 Jurneke Joe K Dynamic skew compensation systems and associated methods
US20060209450A1 (en) * 2005-03-18 2006-09-21 Quantum Corporation Auto-servo tape system and associated recording head
US20080198503A1 (en) * 2005-03-18 2008-08-21 Quantum Corporation Auto-servo tape system and associated recording head
US7499235B2 (en) 2005-03-18 2009-03-03 Quantum Corporation Auto-servo tape system and associated recording head
US7649707B2 (en) 2005-03-18 2010-01-19 Quantum Corporation Auto-servo tape system and associated recording head
US20080266705A1 (en) * 2007-04-25 2008-10-30 Quantum Corporation Servo error detection and compensation utilizing virtual data tracking servo methods
US7826169B2 (en) 2007-04-25 2010-11-02 Quantum Corporation Servo error detection and compensation utilizing virtual data tracking servo methods

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